The linear motion guide units are increasingly needed in years to have greater improvements in function and get more befitted to work in tough operating environment by addition of optional accoutrements or attachments including dustproof means to prevent foreign material from invading through ends of a slider, highly hermetical seals, lubricators to apply lubricant to the slider, and so on. Especially, the advanced technology in recent years needs the linear motion guide unit adapted for use in machine tools including cutting machines, grinding machines, woodcutting machines, and so on, which operate in harsh working environment where much foreign materials including chips, debris, dirt, dusts, and so on occur or any liquid including processing fluids and so on splashes.
In the commonly-assigned Japanese Laid-Open Patent Application H09-317 765, there is disclosed a linear motion guide unit with a mounting plate to fasten an additional seal on an outward surface of an end seal of a slider to improve the sealing function. The mounting plate is made up of a ceiling portion and sidewise opposite wing portions extending downwards from the widthwise opposite ends of the ceiling portion. The sidewise opposite wing portions have locating pins to locate precisely the additional seal relatively to the slider. Moreover, the mounting plate has holes into which fastening screws fit to secure the mounting plate onto the slider and further has tapped holes into which threaded screws fit to hold a scraper plate or sealing member thereon. The mounting plate also serves as a spacer.
However, the mounting plate used in the prior linear motion guide unit constructed as stated just earlier, because of machined out of a steel blank uniquely to every linear motion guide unit, has required considerable effort in processing steps and expense in production thereof. Moreover, the prior mounting plate functions only as a spacer to provide a mounting surface at a location around a lip part protruding above the outward end surface of the end seal and therefore may be relatively moderate in accuracy.
Meanwhile, the linear motion guide units finding increased application are especially required meeting with the maintenance-free operation for lubrication and high-accuracy working even with high functional burden, further keeping running cost and maintenance cost for long-lasting service life reasonable. The majority of modern linear motion guide unit is the roller type more preferable in stiffness and accuracy. The advanced technology is in need of the linear motion guide unit that is not only able to operate better in worse working environment, but also more refined in function with the slider being mounted at the end surface thereof with any optional ancillary including dustproof means to prevent foreign material from invading through ends of a slider, highly hermetical seals, lubricators to apply lubricant to the slider, and so on. To this end, although there is provided a mounting plate to retain the accoutrements on the slider, the mounting plate is desired to be easier and steadier in its installation on the slider and also high in accuracy and less in production cost. On the other hand, the linear motion guide units, since finding in years diverse applications in machine tools and so on used in tough working environment, are required to stand up to the harshest conditions where much foreign materials including chips, debris, dirt, dusts, and so on occur or any liquid including processing fluids, and so on splashes.